The oil industry began in 1859 with the drilling of the first oil well production and operation of the first refinery two years later. Since then the refining processes and transportation have evolved as obtaining commercial hydrocarbons, seeking to reduce environmental effects (OSHA Technical Manual).
Pipelines constructed of low carbon steel as the main means of transport of hydrocarbons, among others, crude oil, gasoline, middle distillates and oxygenates, are expose to corrosive agents such as H2S, CO2, O2, H2O, organic acids and soluble salts. Similarly, due to the characteristics of the land where these pipelines are installed, they undergo drastic operating conditions, which have corrosion problems both external surfaces as internal. With regard to internal corrosion, ways to mitigate damage include mechanical cleaning and the use of corrosion inhibitors. Therefore, inhibitors require high efficiency to control corrosion.
The main type of corrosion, which occurs in the ducts (those carrying hydrocarbons) is uniform and localized corrosion observed as corrosion products sulfides and iron oxides. The main allotropic form of iron oxides is hematite; while for the case of sulfides are pyrite.
Moreover globally, and in order to control the problems of internal corrosion that occur in pipelines, they have been mainly used corrosion inhibitors that have the peculiarity to function properly in environments where the main corrosion products are iron oxides. In addition, the establishment of strict environmental criteria governing the application of inhibitors has resulted in several types of chemicals that were used as a basis to produce corrosion inhibitors, are removed from use for failing to meet environmental criteria established worldwide. In addition to this, in ducts where hydrocarbons have been transporting by ships, it has detected the presence of high amounts of water and inorganic salts that generate deposit corrosion under. Given the above facts, it is necessary that new inhibitors efficiently controlling corrosion problems that occur in the ducts, which are environmentally friendly and economically competitive.
The corrosion inhibitors are required in low concentration between 3 to 7 ppm, are able to control problems uniform corrosion that occurs in pipelines carrying hydrocarbons. It is important that these inhibitors also control problems uniform and localized corrosion that occurs, under high turbulence in the pipelines with high water content such as the so-called “playeros”.
The company Petroleos Mexicanos (PEMEX) produces about 2.548 million barrels per day (bpd) of crude oil, of which 1,199 Mbd are processed in its refineries producing different fuels and oxygenated hydrocarbons, which are transported on its 40,106 Km length piping. Also, other products from the United States are processed (Yearbook PEMEX 2013). The transported hydrocarbons include to a greater or lesser degree gases such as CO2, H2S and O2, contaminated with salts or even with complex agents, which generate corrosion on such ducts.
Flow Changes in pipelines alter the operating conditions, which lead to differences in pH, affecting the corrosion rates of materials. Other factors affecting the process of corrosion of pipelines is the change of temperature, flow rate, pressure, etc. (Materials Performance, August 2002 16-21 and Corrosion Science, 49, 2007, 4308-4338). The problem is that there is not a universal corrosion inhibitor able to protect materials from all corrosive compounds existing in the different currents. Since we do not have such an inhibitor, at least we must have one to protect from the main transported currents.
By the end of 1930, the main storage containers of fuel were manufactured of metals such as steel, aluminum, brass, zinc and other. They suffered corrosion damage because fuel was contaminated with considerable amounts of water, so the use of water-based corrosion inhibitors such as sodium uranates (U.S. Pat. No. 2,205,754), were continuously added to the tanks. Subsequently they were used organic compounds as those obtained from the reaction product of an alkyl amine and saturated aliphatic carboxylic acid, as those presented in the U.S. Pat. No. 2,330,524.
Furthermore, by the 1950 in several researches it were showing that, inhibitors in their structure have a polar part and a hydrocarbon chain is straight or branched. For imidazolines, these have three components; a ring or head, a tail long chain hydrocarbon and a side chain attached to the head, which may be a short chain hydrocarbon with active or polar functional group (Corrosion Science, 36.1994, 315-325).
The realization of our literature search was focusing mainly on the imidazolines as our new development emphasizes obtaining these imidazolines new structure based on their starting materials and their preparation process. Examples of structures imidazole is U.S. Pat. No. 2,668,100, for use as corrosion inhibitors in gasoline, diesel and fuel oil. lmidazoline have the following general formula shown in the diagram (2):

The imidazoline is a derivative of salicylic acid where R in position 2, is an aliphatic group containing from 13 to 17 carbon atoms.
U.S. Pat. Nos. 3,623,979 and 3,758,493, indicate that the inhibitor is a condensation product of a polymeric acid and 1-aminoalkyl-2-alkyl-2-imidazoline whose formula is represented in the scheme (3):
this compound is soluble and dispersible in the brine, which can be applied continuously or intermittently, wherein: R is a fatty acid of tall oil that is an alkyl radical of 17 to 32 carbon atoms. The fatty acid of tall oil, is a compound obtained as a byproduct in the manufacture of paper pulp from conifers, by the Kraft process. The composition is a mixture of about 50% resin acids, 35% palmitic, oleic and linoleic acids and unsaponifiables 15% as heavy hydrocarbons, higher alcohols and sterols; A is a bivalent radical of ethylene; m is 1 to 5; n may be 2 to 4 which indicates the basicity of the polymeric acid; and R′ is an alkyl radical of a polymeric acid of 15 to 70 carbon atoms.
Tall oil acids may be linoleic, stearic or a combination of linoleic and oleic cuts. Amines for forming imidazoline may be diethylenetriamine, triethylenetetramine and tetraethylenepentamine. It is noted that the U.S. Pat. No. 3,758,493 patent reports the use of dimer or trimer fatty acids or a polymeric high molecular weight fatty acid instead of tall oil.
Summarizing found in patents U.S. Pat. No. 3,846,071, CA 1,178,578, U.S. Pat. No. 4,388,214, EP 526.251 A1, U.S. Pat. Nos. 5,322,630, 5,214,155, 5,322,640 and 6,448,411 B1. The radicals attached to the imidazoline are hydrocarbon chains alkenyl or Alkyl, which may range from 7 to 25 carbon atoms. These chains are mainly of oleic acid and tall oil fatty acid. Throughout the literature review was conducted, obtaining imidazolines from an amine such as diethylenetriamine (DETA), triethylenetetramine (TETA) and tetraethylenepentamine (TEPA), with the fatty acid of tall oil, is the most common method obtaining imidazoline.
The chemical structure of oleic acid has 18 carbon atoms with a ligature, as shown in the following scheme (4):

At one end of this molecule we found the carboxylic group and half of the hydrocarbon chain have a double bond.
Vegetable oil is an organic compound obtained from seeds or other plant parts. These products offered in the market are pure edible oil and edible vegetable oil. The pure edible oil is obtain from one type of plant; when it is a mixture of oils, the product is call edible vegetable oil. Although there are a variety of plants from which vegetable oil is extract, the main are safflower, corn, sesame, sunflower, cotton, soybean, olive, canola and others. The most frequent (solid) fats or oils (liquids) are a mixture of triglycerides with minor amounts of other lipids. Triglycerides are the most abundant family of lipid and the main fuel reserve, the general formula of these triglycerides shown in the following scheme (5):

Glycerol is capable of binding to three fatty acid radicals called carboxylates. These fatty radicals usually are different from each other; they may be saturated or unsaturated. Extension chain fatty radicals R1, R2 and R3 may be from 12 to 24 carbon atoms. Exist in nature at least 50 fatty acids (J. Am Oil Chem. Soc. (2009) 86, 991), on the other hand these chains can be saturated or unsaturated, so that we can have from 1 to 3 unsaturations that give the liquid characteristic at room temperature.
As is known, saturated fats like butter and beef are those that increase cholesterol in humans, while polyunsaturated fats help lower cholesterol (Nutrition Action Health letter July/2002 August 3). In FIG. 1 is plotted the type of oil and its composition based on the degree of saturation of each oil, so that as it descends from the list decreases saturated compounds and increasing the percent of unsaturation oils. An oil with less saturated groups is better, and it is preferable that the oil has omega-3 fat (polyunsaturated) which can protect the heart, the latter three compounds is flaxseed oil, which has higher content of omega 3. On an industrial scale combinations are made in order to obtain products with better taste and health benefits.